1. Field of the Invention
This invention relates to a labelling machine, in particular, a labelling machine for the labelling of objects of different diameters having cylindrical labelling surfaces, such as bottles, which can be moved on rotatable plates of a turntable past a labelling station or a marking station. Each rotatable plate is rotationally controlled by means of a translation transmission by a pivoting control lever arm guided in a stationary cam, whereby the cam has a removable cam segment.
2. Background Information
A labelling machine having these features is disclosed, for example, by German Laid Open Patent Application No. 36 22 179. On this and similar labelling machines, the segment of the cam located next to the labelling station can be removed and replaced, so that a cam segment having a rotational program corresponding to the containers to be labelled can be inserted. The switch from one program to another requires both a conversion process and inventory of an appropriate number of cam segments.
On the labelling machine disclosed German Laid Open Patent application No. 36 22 179, the replaceable cam segment fits into the corresponding recess in the cam, forming a butt joint interface. Jerking movements are caused if the cam roller, when running past the interface, jumps out of the cam path in the cam into the cam path of the cam segment. As a result of dimensional tolerances, an offset is unavoidably formed in the path at the intersection of the cam and the cam segment. At the interface, a dimensional variance in the form of a recess or a projection leads to a step or shoulder in the cam path. When the cam roller passes the interface, any differences in height in the course of the cam path causes a jerk-like divergence in the movement of the cam roller. This leads to an increase in wear of the cam rollers and the cam path, and is also extremely undesirable as it prohibits a precise application of a label at the label station, which is generally located a short distance beyond the interface. The uniform movement of the bottle rotatable plate being guided by the cam roller is disrupted, leading to vibrations which are transmitted to the bottle. The proper application of the label is therefore no longer guaranteed.